using System.Text;

public class ExcelUtil
{
    public static string ToFirstUpper(string s)
    {
        var firstChar = s.Substring(0, 1);
        s = firstChar.ToUpper() + s.Substring(1);
        return s;
    }

    public static string ToFirstLower(string s)
    {
        var firstChar = s.Substring(0, 1);
        s = firstChar.ToLower() + s.Substring(1);
        return s;
    }
    
    public static void AddIndentation(StringBuilder sb, int indentation, int tabSpaceCount)
    {
        for (int i = 0; i < indentation; i++)
        {
            for (int j = 0; j < tabSpaceCount; j++)
            {
                sb.Append(" ");
            }
        }
    }
}
